1 /* eval.h header file for eval.c 2 * 3 * The Netwide Assembler is copyright (C) 1996 Simon Tatham and 4 * Julian Hall. All rights reserved. The software is 5 * redistributable under the licence given in the file "Licence" 6 * distributed in the NASM archive. 7 */ 8 9 #ifndef YASM_EVAL_H 10 #define YASM_EVAL_H 11 12 /* 13 * ------------------------- 14 * Error reporting functions 15 * ------------------------- 16 */ 17 18 /* 19 * An error reporting function should look like this. 20 */ 21 typedef void (*efunc) (void *private_data, int severity, const char *fmt, ...); 22 23 /* 24 * These are the error severity codes which get passed as the first 25 * argument to an efunc. 26 */ 27 28 #define ERR_DEBUG 0x00000008 /* put out debugging message */ 29 #define ERR_WARNING 0x00000000 /* warn only: no further action */ 30 #define ERR_NONFATAL 0x00000001 /* terminate assembly after phase */ 31 #define ERR_FATAL 0x00000002 /* instantly fatal: exit with error */ 32 #define ERR_PANIC 0x00000003 /* internal error: panic instantly 33 * and dump core for reference */ 34 #define ERR_MASK 0x0000000F /* mask off the above codes */ 35 #define ERR_NOFILE 0x00000010 /* don't give source file name/line */ 36 #define ERR_USAGE 0x00000020 /* print a usage message */ 37 #define ERR_PASS1 0x00000040 /* only print this error on pass one */ 38 39 /* 40 * These codes define specific types of suppressible warning. 41 */ 42 43 #define ERR_WARN_MASK 0x0000FF00 /* the mask for this feature */ 44 #define ERR_WARN_SHR 8 /* how far to shift right */ 45 46 #define ERR_WARN_MNP 0x00000100 /* macro-num-parameters warning */ 47 #define ERR_WARN_MSR 0x00000200 /* macro self-reference */ 48 #define ERR_WARN_OL 0x00000300 /* orphan label (no colon, and 49 * alone on line) */ 50 #define ERR_WARN_NOV 0x00000400 /* numeric overflow */ 51 #define ERR_WARN_GNUELF 0x00000500 /* using GNU ELF extensions */ 52 #define ERR_WARN_MAX 5 /* the highest numbered one */ 53 54 /* 55 * The expression evaluator must be passed a scanner function; a 56 * standard scanner is provided as part of nasmlib.c. The 57 * preprocessor will use a different one. Scanners, and the 58 * token-value structures they return, look like this. 59 * 60 * The return value from the scanner is always a copy of the 61 * `t_type' field in the structure. 62 */ 63 struct tokenval { 64 int t_type; 65 yasm_intnum *t_integer, *t_inttwo; 66 char *t_charptr; 67 }; 68 typedef int (*scanner) (void *private_data, struct tokenval *tv); 69 70 /* 71 * Token types returned by the scanner, in addition to ordinary 72 * ASCII character values, and zero for end-of-string. 73 */ 74 enum { /* token types, other than chars */ 75 TOKEN_INVALID = -1, /* a placeholder value */ 76 TOKEN_EOS = 0, /* end of string */ 77 TOKEN_EQ = '=', TOKEN_GT = '>', TOKEN_LT = '<', /* aliases */ 78 TOKEN_ID = 256, TOKEN_NUM, TOKEN_REG, TOKEN_INSN, /* major token types */ 79 TOKEN_ERRNUM, /* numeric constant with error in */ 80 TOKEN_HERE, TOKEN_BASE, /* $ and $$ */ 81 TOKEN_SPECIAL, /* BYTE, WORD, DWORD, FAR, NEAR, etc */ 82 TOKEN_PREFIX, /* A32, O16, LOCK, REPNZ, TIMES, etc */ 83 TOKEN_SHL, TOKEN_SHR, /* << and >> */ 84 TOKEN_SDIV, TOKEN_SMOD, /* // and %% */ 85 TOKEN_GE, TOKEN_LE, TOKEN_NE, /* >=, <= and <> (!= is same as <>) */ 86 TOKEN_DBL_AND, TOKEN_DBL_OR, TOKEN_DBL_XOR, /* &&, || and ^^ */ 87 TOKEN_SEG, TOKEN_WRT, /* SEG and WRT */ 88 TOKEN_FLOAT /* floating-point constant */ 89 }; 90 91 /* 92 * The actual expression evaluator function looks like this. When 93 * called, it expects the first token of its expression to already 94 * be in `*tv'; if it is not, set tv->t_type to TOKEN_INVALID and 95 * it will start by calling the scanner. 96 * 97 * `critical' is non-zero if the expression may not contain forward 98 * references. The evaluator will report its own error if this 99 * occurs; if `critical' is 1, the error will be "symbol not 100 * defined before use", whereas if `critical' is 2, the error will 101 * be "symbol undefined". 102 * 103 * If `critical' has bit 8 set (in addition to its main value: 0x101 104 * and 0x102 correspond to 1 and 2) then an extended expression 105 * syntax is recognised, in which relational operators such as =, < 106 * and >= are accepted, as well as low-precedence logical operators 107 * &&, ^^ and ||. 108 */ 109 #define CRITICAL 0x100 110 typedef yasm_expr *(*evalfunc) (scanner sc, void *scprivate, struct tokenval *tv, 111 int critical, efunc error, yasm_symtab *symtab); 112 113 /* 114 * The evaluator itself. 115 */ 116 yasm_expr *evaluate (scanner sc, void *scprivate, struct tokenval *tv, 117 void *eprivate, int critical, efunc report_error, 118 yasm_symtab *symtab); 119 120 #endif 121